Researchers found that smokers admitted to the intensive care unit (ICU) who received nicotine replacement therapy (NRT) during their stay had a higher risk of death than smokers who did not receive NRT. "In some critically ill patients, the development of nicotine withdrawal symptoms can worsen their prognosis. As a result, NRT is given to active smokers in the ICU to prevent nicotine withdrawal symptoms," said lead researcher Amy Lee, MD, Mayo Clinic College of Medicine, Minneapolis. "The haemodynamic effects of nicotine may lead to increased heart rate, systemic arterial blood pressure, and constriction of the coronary arteries. Although these potential adverse effects of NRT have not been shown to worsen the prognosis of healthy volunteers and patients with stable coronary artery disease, they may be detrimental in critically ill patients."

Lee and colleagues examined the safety of NRT in the ICU by reviewing the medical records of 112 smoking patients admitted to the ICU who received NRT during their stay. Among the patients who received NRT, 18 deaths (16.1%) occurred, compared with the three deaths (2.7%) in the control group. The hospital mortality rate was 21.4% for the NRT group, compared with 5.4% in the control group. Furthermore, when researchers controlled for severity of illness, NRT was found to be an independent risk factor for mortality (odds ratio 17.0).

"Although administering nicotine replacement therapy to smokers in the ICU is not a standard practice, some ICUs have nurse-driven protocols aimed at providing NRT for active smokers. We expect NRT to be more widely used in such ICUs," said senior author Bekele Afessa, MD, FCCP, Mayo Clinic College of Medicine.